English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Nucleation-mediated reshaping of facetted metallic nanocrystals: Breakdown of the classical free energy picture

MPS-Authors
/persons/resource/persons257607

Lai,  King Chun
Theory, Fritz Haber Institute, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)

5.0138266.pdf
(Publisher version), 8MB

Supplementary Material (public)
There is no public supplementary material available
Citation

Lai, K. C., Liu, D.-J., & Evans, J. W. (2023). Nucleation-mediated reshaping of facetted metallic nanocrystals: Breakdown of the classical free energy picture. The Journal of Chemical Physics, 158(10): 104102. doi:10.1063/5.0138266.


Cite as: https://hdl.handle.net/21.11116/0000-000C-F805-7
Abstract
Shape stability is key to avoiding degradation of performance for metallic nanocrystals synthesized with facetted non-equilibrium shapes to optimize properties for catalysis, plasmonics, and so on. Reshaping of facetted nanocrystals is controlled by the surface diffusion-mediated nucleation and growth of new outer layers of atoms. Kinetic Monte Carlo (KMC) simulation of a realistic stochastic atomistic-level model is applied to precisely track the reshaping of Pd octahedra and nanocubes. Unexpectedly, separate constrained equilibrium Monte Carlo analysis of the free energy profile during reshaping reveals a fundamental failure of the classical nucleation theory (CNT) prediction for the reshaping barrier and rate. Why? Nucleation barriers can be relatively low for these processes, so the system is not locally equilibrated before crossing the barrier, as assumed in CNT. This claim is supported by an analysis of a first-passage problem for reshaping within a master equation framework for the model that reasonably captures the behavior in KMC simulations.